An important factor during dental examinations or procedures is proper illumination inside the patient's oral cavity. Proper illumination of the oral cavity is difficult to achieve for such varied reasons as, for example, the opening of the patient's mouth is reduced, the dentist is placed between the light and the patient's mouth, and the dentist also introduces his or her hand with the instruments to carry out the treatments and examinations.
Conventionally, the patient's oral cavity is illuminated by means of a light located above the dental chair, which is located approximately 1 m from the patient's back. The source of light is focused toward the patient's mouth, but most of the illumination provided is wasted because the dentist, in being very close to the patient's buccal cavity, blocks a great part of the light emitted with his or her head. Another part of the illumination is also blocked by the dentist's hand that manipulates the instruments and by the instruments themselves, thus generating many shadows and thereby greatly limiting the amount of light that can arrive in the interior of the patient's mouth. An additional factor leading to poor illumination of the oral cavity resides in the morphological factor of the buccal cavity, given which it is impossible to obtain proper illumination unless the dentist and the patient adopt very uncomfortable positions for long periods with the objective of allowing the passage of light and thus obtaining proper illumination. The solution to these problems of blocking the source of illumination consists of devising a way to place the source of illumination inside the oral cavity with the objective of eliminating this series of shadows.
Several ways to solve the problem of blocking the illumination can be found in the state of the technology. For example, U.S. Pat. Nos. 1,122,086; 1,094,575; 2,201,331; 1,998,374; 2,528,458; 2,800,896; and 3,171,203 disclose systems of illumination that solve the problem of blocking the illumination, but at the same time, present such new inconveniences as, for example, being voluminous and using focused incandescence, which generates a great deal of heat.
One technology that focused on solving the problem of heat-generation and providing a solution to the problem of intraoral illumination concerns the use of fiber optics. In general, systems of illumination by means of fiber optics have the same principle and consequently, possess the same defects. As is known by a person skilled in the art, a system of illumination by means of fiber optics is basically made up of a light source and one or more optical fibers. The light source requires high energy consumption to generate sufficient intensity and because of this, generates a great amount of heat and thus needs a cooling system. This makes the light source a voluminous and annoying apparatus.
Optical fiber is a coherent light-conducting material that presents great longitude, but with a small cross section, and this means that the light source can be far from the work area and that a certain quantity of light can transported by means of the fiber to the workspace. Although optical fibers are efficient in the conduction of light, their greatest inconvenience resides in the fact that they are very fragile and break easily. Another inconvenience is that optical fiber presents an attenuation coefficient that rises if the fiber is bent, meaning that the fibers should present large radii of curvature, and this inhibits their manipulation. That is, if a fiber bends too much, the attenuation of the conducted light will become significant, and as a consequence, reduce the intensity of the conducted light. A further disadvantage that optical fibers exhibit is their small cross section, which produces a limited field of illumination, without mentioning the difficulty in splicing these fibers. In addition to the expensive equipment and special facilities that the implementation of fiber optic technology requires, there is [also] inconvenience in handling, and the fibers tend to deteriorate with cycles of sterilization.
Examples of the first fiber optic illumination systems adapted for dental instruments are described in U.S. Pat. Nos. 3,590,232; 3,614,415; 3,616,792; 3,638,013; 3,758,951 and 5,281,134.
Examples of fiber optic illumination systems included as part of dental instruments are disclosed in, for example, U.S. Pat. Nos. 2,359,828; 3,397,457; 3,614,414; 3,634,938; 4,233,649; 4,629,425; 4,992,047; 5,457,611; 5,462,435; 5,512,686. All these designs of instruments with fiber optic illumination systems are limited to the illumination of a small area of the oral cavity and they have the disadvantages mentioned previously for the use of fiber optics.
U.S. Pat. No. 5,931,670 describes a saliva extractor illuminated by fiber optic means that includes a diffuser provided in the tip of the extractor wherein the illumination system presents the disadvantages attending the use of fiber optics.
The publication of United States of America Patent Series Application No. 2005/0227133 A1 describes a combination of lip retractor and saliva extractor in which a fiber optic illumination system can be incorporated, with the inconveniences involved in the use of this fiber optic technology.
U.S. Pat. Nos. 3,916,880 and 4,592,344, both of Schroer, describe a lip retractor that comprises a fiber optic illumination system located in both corners of the oral cavity. The lip retractor with illumination system disclosed by Schroer can provide general illumination of the oral cavity, but it has the disadvantages mentioned of fiber optics and it requires, moreover, structures especially designed to house the fiber optics.
In U.S. Pat. Nos. 6,022,214; 6,338,627; 6,575,746; and 6,908,308; all granted to Hirsch et al., an intraoral illumination device is disclosed that comprises a bite block and a light-dispersing piece connected to the bite block. The device also includes a tongue and cheek retractor, as well as channels of fluid evacuation. The light-dispersing piece provides illumination to the greater part of the oral cavity. The device presents the inconvenience of being voluminous and of complex construction, because of which, part of the arch is hidden beneath the bite block and that area cannot be reviewed or examined. Moreover, because the illumination used in this device is provided by means of fiber optics, the device possesses the disadvantages inherent to the use of fiber optics.
U.S. Pat. No. 4,872,837 discloses a surgical or dental instrument capable of providing illumination. The instrument includes, among other parts, a stem of transparent material intended to aspirate, clean, dry off and illuminate, wherein the wall of the stem is used as a conductive means of light. Nevertheless, this instrument has the inconvenience that the area of illumination is very limited.
U.S. Pat. No. 6,332,776 discloses a bite block that makes use of a reflected light source of optic or internal fiber to illuminate the mouth, and the publication of United States of America Patent Application No. 2005/0239017 is related to another bite block design in ring form that is used as a diffuser of microfluorescent light; however, both bite block designs hide part of the patient's arch and therefore, make the review and examination of these areas impossible.
U.S. Pat. Nos. 4,643,172 and 4,807,599 describe illuminating tongue depressors that comprise a means to concentrate and direct the light where said means is used as a diffuser that would be very useful for a review procedure since only a defined area of the mouth is illuminated, and therefore, it is not capable of illuminating the intraoral cavity for a treatment since it requires holding the tongue depressor while the dentist is working, which means the assistant loses a hand that could be used to help the dentist.
In U.S. Pat. No. 6,607,384, Nakanishi describes an illumination device to be used with a dental or medical instrument for treatment of a site. The illumination device includes a series of light-emitting diodes (LED) provided in a hoop-shaped LED holder that is placed in the distal part of the dental instrument such as, for example a drill. The illumination device is mounted on the drill by means of grips that clasp the neck of the drill in a such way that this passes through the holder where the LEDs are located in the periphery of the drill. When the LEDs emit light, this light is irradiated from the distal end of the drill in all directions, avoiding shadows in the same. This illumination device is excellent when preparing a cavity, but because the light is mounted on the instrument, when the instrument is withdrawn from the mouth, the dentist will be without light and when working with another instrument that does not have this illumination device, he or she will continue working under the usual (faulty) conditions of illumination
Nakanishi suggests that this illumination device can be mounted on any instrument; most of the instruments in a dental clinic are for straight work (98%); that is, the working tip of the instrument corresponds to the axial axis of the dentist's hand (that is, the axial axis of the hand and the working direction of the instrument are parallel). The remaining 2% of instruments include the high-speed handpiece and the low-speed contra-angle (“two instruments”) that are for angled work, that is, the working tip of the instrument forms an angle with respect to the axial axis of the dentist's hand (that is, the working direction of the instrument is perpendicular to the axial axis of the dentist's hand). Nevertheless, the direction of the light provided by Nakanishi's illumination device is parallel to the direction of the attachment grips that clasp the neck of the instrument, and this implies that when the illumination device is placed on an instrument, the direction of the light will be perpendicular to it. It is thus impossible to work with this addition placed on a straight instrument. Therefore, the device disclosed by Nakanishi can only be placed on 2% of the instruments, since 98% of instruments are straight, and because of this, the device does not satisfy 100% of the need for illumination of the intraoral cavity required by the dentist.
An illumination device of the oral cavity provided in a bite block that consists of light-emitting diodes (LED), is described in U.S. Pat. No. 6,830,451 and in the publication of United States of America Patent Application No. US2005/0239018. As described, the illumination in the bite block is provided by means of a series of LEDs provided on the lateral or lingual face of the bite block in such a way that the light is emitted laterally. The illumination provided by this device lights the upper and right inferior quadrants from the left side and vice versa. The feed source for the illumination device is by means of batteries that are contained inside the bite block. This type of device presents some inconveniences, such as, for example, when emitting the light laterally what is illuminated is really the lingual faces of the teeth opposite, but the occlusal faces would be moderately illuminated, while the vestibular faces would not be illuminated. Thus, it is impossible for this illumination device to be useful in illuminating the interior of the preparation of a tooth. Another inconvenience in the illumination device of U.S. Pat. No. 6,830,451 and publication US2005/0239018, resides in the necessity that the patient have the entirety of his or her back dental pieces, upper as well as lower, because this device cannot be used in a patient who lacks molars, either upper or lower, as the device rests on their occlusal faces.
The publication of the United States of America Patent Application No. US2004/0063060 describes an illumination device of the oral cavity, which is placed on the molars to provide illumination in the interior. The device includes a battery, a band, a light source and a means to secure the device to the molars with temporary cement, or to anchor to brackets, or to an orthodontic band that is in itself an inconvenience.
In accordance with the foregoing, a necessity exists in the state of the technology for an illumination device of the intraoral cavity that provides efficient illumination of the entirety of the oral cavity. An additional necessity exists for an illumination device of the oral cavity that does not get in the way of work and that allows any type of treatment to be carried out without respect to the instruments being used or where they are used. Yet another necessity exists in the state of the technology for an illumination device of the oral cavity that is not complicated to install and is reasonable in cost. For these reasons, an object of the present invention is to provide a device for illumination of the oral cavity that is economical and easily managed, and that does not require special structures and facilities.
Another object of the present invention is to provide a device for illumination of the oral cavity that efficiently illuminates the lingual, occlusal and vestibular faces.
Yet another object of the present invention consists of providing a device for illumination of the oral cavity that can be placed in a commercial cheek retractor.
A further object of the present invention is to provide a device for unilateral or bilateral illumination of the oral cavity so that the dentist can obtain total or partial illumination.
An additional object of the present invention is to provide a device for illuminating the oral cavity that allows the dentist to regulate the intensity of the illumination in each upper and lower quadrant independently.
A further object of the present invention is to provide a device for unilateral or bilateral illumination of the oral cavity.
Yet another object of the present invention is to provide a novel bite block design to implement the device for lateral illumination of the oral cavity.